Re:Lilium – Electric vertical take-off and landing jet
by andars on Friday April 21, 2017 @04:47PM
(#14169313)
Maybe, but unlikely. Lasers need line of sight and would generally be a bad idea at the power levels required (basically a weapon), and microwave power transmission requires large receiving apertures. Current "wireless charging" technologies are pretty much universally near field.
Re:Lilium – Electric vertical take-off and landing jet
by nradov on Friday April 21, 2017 @04:46PM
(#14169308)
Impossible for safety reasons in populated areas. And even ignoring safety issues, the conversion efficiency on beamed power is so low as to make it uneconomical.
Re:Lilium – Electric vertical take-off and landing jet
by stcredzero on Friday April 21, 2017 @05:09PM
(#14169446)
I thought the conversion efficiency for microwaves was 80%.
Re:Lilium – Electric vertical take-off and landing jet
by nradov on Friday April 21, 2017 @05:40PM
(#14169641)
Maybe in a kitchen microwave oven. You're not accounting for transmission path losses and receiver conversion efficiency.
Re:Lilium – Electric vertical take-off and landing jet
by stcredzero on Friday April 21, 2017 @08:04PM
(#14170394)
Actually, I think that's a figure including transmission and receiver conversion efficiency, but it doesn't include path losses. That's still quite impressive, though.
http://spectrum.ieee.org/energywise/green-tech/solar/japan-d...
Re:Lilium – Electric vertical take-off and landing jet
by nradov on Friday April 21, 2017 @09:39PM
(#14170689)
That's for short range transmission to a fixed receiver. So not really relevant for powering aircraft.
Re:Lilium – Electric vertical take-off and landing jet
by stcredzero on Saturday April 22, 2017 @10:18PM
(#14176085)
Such microwave systems have been proposed for solar power satellites. They have useful ranges up to 100's of miles.
Re:Lilium – Electric vertical take-off and landing jet
by pdelbarba on Friday April 21, 2017 @05:24PM
(#14169547)
How would this work through clouds? The water vapor would in theory block or scatter everything from UV to microwave radiation. Also, I don't want to be near a 1W laser/maser, and if our energy budget is 100kW, you'd need at least a 100,000W laser pointed at your tiny air taxi.
Beamed power?